1. Field of the Invention
This invention relates to a display device, and more particularly to a liquid crystal display device and a driving method thereof.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) controls light transmittance of a liquid crystal using an electric field to thereby display a picture. To this end, the LCD device includes a liquid crystal display panel having a pixel matrix, and a driving circuit for driving the liquid crystal display panel. The driving circuit drives the pixel matrix such that picture information can be displayed on the display panel.
FIG. 1 shows a related art liquid crystal display device. As shown in FIG. 1, the related art LCD device includes a liquid crystal display panel 2, a data driver 4 for driving data lines DL1 to DLm of the liquid crystal display panel 2, and a gate driver 6 for driving gate lines GL1 to GLn of the liquid crystal display panel 2. The liquid crystal display panel 2 includes a thin film transistor TFT at each intersection between the gate lines GL1 to GLn and the data lines DL1 to DLm that define liquid crystal cells arranged in a matrix type. Each of the liquid crystal cells includes a pixel electrode connected to the thin film transistor TFT of a respective liquid crystal cell.
The gate driver 6 sequentially applies a gate signal to each gate line GL1 to GLn in response to a control signal from a timing controller (not shown). The data driver 4 converts data R, G and B from the timing controller into analog video signals to thereby apply video signals to the data lines DL1 to DLm for one of the horizontal lines during every horizontal period when a gate signal is applied to each gate line GL1 to GLn. More particularly, the thin film transistor TFT applies data from the data lines DL1 to DLm to the liquid crystal cell in response to a control signal from the gate lines GL1 to GLn.
The liquid crystal cell can be equivalently expressed as a liquid crystal capacitor Clc because it includes a common electrode and a pixel electrode opposed to each other with a liquid crystal material therebetween. The pixel electrode is connected to the thin film transistor TFT. The liquid crystal cell also includes a storage capacitor (not shown) connected to a pre-stage gate line in order to keep a data voltage charged on the liquid crystal capacitor Clc until the next data voltage is charged therein.
The liquid crystal cells of such a related art LCD device has vertical lines equal to the number (i.e., m) of the data lines DL1 to DLm because they are provided at intersections between the gate lines DL1 to DLn and the data lines DL1 to DLm. In other words, the liquid crystal cells are arranged in a matrix type in such a manner to make m vertical lines and n horizontal lines. The related art LCD device requires m data lines DL1 to DLm so as to drive the liquid crystal cells having m vertical lines. Therefore, the related art LCD device has a drawback in that a number “m” of data lines DL1 to DLm should be provided to drive the liquid crystal display panel 2. Thus, processing time and a manufacturing cost are large. Furthermore, the related art LCD device has a problem in that, since a large number of data drive integrated circuits (IC's) are included in the data driver 4 so as to drive the m data lines DL1 to DLm, a large manufacturing cost is required.